Electroacupuncture Pretreatment Alleviates Cerebral Ischemic Injury Through α7 Nicotinic Acetylcholine Receptor-Mediated Phenotypic Conversion of Microglia
Electroacupuncture Pretreatment Alleviates Cerebral Ischemic Injury Through α7 Nicotinic Acetylcholine Receptor-Mediated Phenotypic Conversion of Microglia
复制标题
电针预处理通过 α7 烟碱乙酰胆碱受体介导的小胶质细胞表型转化减轻脑缺血损伤
DOI：
10.3389/fncel.2019.00537
复制
发表时间：
2019-12-06
影响因子：
5.3
通讯作者：
Wang, Qiang
中科院分区：
文献类型：
--
作者：
Ma, Zhi;Zhang, Zengli;Wang, Qiang
电针预处理通过α 7烟碱型乙酰胆碱受体（α 7 nAChR）减轻脑缺血损伤。我们试图通过α 7 nAChR研究小胶质细胞表型转化是否参与电针预处理对脑缺血的治疗作用。成年雄性Sprague-Dawley（SD）大鼠经EA或α 7 nAChR激动剂N-（3R）-1-氮杂双环[2.2.2]辛-3-基-呋喃并[2，3-c]吡啶-5-甲酰胺盐酸盐（PHA-543，613 hydrochloride）和拮抗剂α-银环蛇毒素（α-BGT）预处理后，造成大脑中动脉闭塞（MCAO）。原代小胶质细胞进行药物预处理和氧-葡萄糖剥夺（OGD）。经典活化表型（M1）小胶质细胞标志物诱导的一氧化氮合酶（iNOS）、白细胞介素-1 β（IL-1 β）（IL-1 β）和分化簇86（CD 86）;替代活化表型（M2）小胶质细胞标志物β-内酰胺酶-1（Arg-1）、转化生长因子β 1（TGF-β 1）（TGF-β 1）和分化簇206（CD 206）;以及促炎细胞因子肿瘤坏死因子-α（TNF-α），白细胞介素-6（IL-6），分析缺血半暗带或原代小胶质细胞上清液中的抗炎细胞因子白细胞介素-4（IL-4）和白细胞介素-10（IL-10）。再灌注72 h后测定脑梗死体积和神经功能评分。采用CCK-8细胞计数试剂盒和乳酸脱氢酶（LDH）释放试验检测与小胶质细胞共培养的神经元的细胞活力和LDH释放。电针预处理可通过激活α 7 nAChR降低M1标志物（iNOS、IL-1 β和CD 86）和促炎细胞因子（TNF-α和IL-6）的表达，而增加M2标志物（Arg-1、TGF-β 1和CD 206）和抗炎细胞因子（IL-4和IL-10）的表达。电针预处理也能显著缩小梗死体积，改善神经功能缺损。小胶质细胞中α 7 nAChR的激活减轻了OGD对原代小胶质细胞的炎症反应，减轻了与小胶质细胞共培养的神经元的损伤。结论：电针预处理通过α 7 nAChR介导的小胶质细胞表型转化减轻脑缺血损伤，这可能是电针预处理抗脑缺血神经保护作用的新机制。
Electroacupuncture (EA) pretreatment alleviates cerebral ischemic injury through alpha 7 nicotinic acetylcholine receptor (alpha 7nAChR). We attempted to investigate whether the phenotypic conversion of microglia was involved in the therapeutic effect of EA pretreatment in cerebral ischemia through alpha 7nAChR. Adult male Sprague-Dawley (SD) rats were subjected to middle cerebral artery occlusion (MCAO) after EA or alpha 7nAChR agonist N-(3R)-1-azabicyclo[2.2.2]oct-3-yl-furo[2,3-c]pyridine-5-carboxamide hydrochloride (PHA-543,613 hydrochloride) and antagonist alpha-bungarotoxin (alpha-BGT) pretreatment. Primary microglia were subjected to drug pretreatment and oxygen-glucose deprivation (OGD). The expressions of the classical activated phenotype (M1) microglia markers induced nitric oxide synthase (iNOS), interleukin-1 beta (IL-1 beta), and cluster of differentiation 86 (CD86); the alternative activated phenotype (M2) microglia markers arginase-1 (Arg-1), transforming growth factor-beta 1 (TGF-beta 1), and cluster of differentiation 206 (CD206); and the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and anti-inflammatory cytokines interleukin-4 (IL-4) and interleukin-10 (IL-10) in the ischemic penumbra or in the supernatant of primary microglia were analyzed. The infarction volume and neurological scores were assessed 72 h after reperfusion. The cell viability and lactate dehydrogenase (LDH) release of neurons co-cultured with microglia were analyzed using cell counting kit-8 (CCK-8) and LDH release assays. EA pretreatment decreased the expressions of M1 markers (iNOS, IL-1 beta, and CD86) and pro-inflammatory cytokines (TNF-alpha and IL-6), whereas it increased the expressions of M2 markers (Arg-1, TGF-beta 1, and CD206) and anti-inflammatory cytokines (IL-4 and IL-10) by activating alpha 7nAChR. EA pretreatment also significantly reduced the infarction volume and improved the neurological deficit. The activation of alpha 7nAChR in microglia relieved the inflammatory response of primary microglia subjected to OGD and attenuated the injury of neurons co-cultured with microglia. In conclusion, EA pretreatment alleviates cerebral ischemic injury through alpha 7nAChR-mediated phenotypic conversion of microglia, which may be a new mechanism for the EA pretreatment-induced neuroprotection against cerebral ischemia.